Azure Function App Using Build.SourceDirectory as working Dir to avoid losing python path

gistfile1.txt

trigger:
- master

variables:
  # Azure Resource Manager connection created during pipeline creation
  azureSubscription: 'conn'

  # Function app name
  functionAppName: 'functestnewtry'

  # Agent VM image name
  vmImageName: 'ubuntu-latest'

  # Working Directory
  workingDirectory: '$(Build.SourcesDirectory)'

stages:
- stage: Build
  displayName: Build stage

  jobs:
  - job: Build
    displayName: Build
    pool:
      vmImage: $(vmImageName)

    steps:
    - bash: |
        if [ -f extensions.csproj ]
        then
            dotnet build extensions.csproj --runtime ubuntu.16.04-x64 --output ./bin
        fi
      workingDirectory: $(workingDirectory)
      displayName: 'Build extensions'
    - task: UsePythonVersion@0
      displayName: 'Use Python 3.6'
      inputs:
        versionSpec: 3.6

    - bash: |
        python -m venv worker_venv
        source worker_venv/bin/activate
        pip install -r requirements.txt
      workingDirectory: $(workingDirectory)
      displayName: 'Install application dependencies'
    - task: ArchiveFiles@2
      displayName: 'Archive files'
      inputs:
        rootFolderOrFile: '$(workingDirectory)'
        includeRootFolder: false
        archiveType: zip
        archiveFile: $(Build.ArtifactStagingDirectory)/$(Build.BuildId).zip
        replaceExistingArchive: true

    - publish: $(Build.ArtifactStagingDirectory)/$(Build.BuildId).zip
      artifact: drop

- stage: Deploy
  displayName: Deploy stage
  dependsOn: Build
  condition: succeeded()

  jobs:
  - deployment: Deploy
    displayName: Deploy
    environment: 'development'
    pool:
      vmImage: $(vmImageName)

    strategy:
      runOnce:
        deploy:

          steps:
          - task: AzureFunctionApp@1
            displayName: 'Azure functions app deploy'
            inputs:
              azureSubscription: '$(azureSubscription)'
              appType: functionAppLinux
              appName: $(functionAppName)
              package: '$(Pipeline.Workspace)/drop/$(Build.BuildId).zip'